//egret example 1
precision lowp float;
varying vec2 vTextureCoord;
varying vec4 vColor;
uniform sampler2D uSampler;

uniform float iTime;

void main(void) {
vec2 uvs = vTextureCoord.xy;
vec4 fg = texture2D(uSampler, vTextureCoord);
float a = fg.a;
fg.rgb += sin(iTime + uvs.x * 2. + uvs.y * 2.) * 0.2;
fg.a = a;
gl_FragColor = fg * vColor;
}
